1. Field of the Invention
The present invention relates generally to weight training devices and, more specifically, to a motorized dumbbell for creating additional tension to provide additional training for a desired muscle group.
2. Description of the Prior Art
Numerous weight training devices have been provided in the prior art. For example, U.S. Pat. Nos. 3,482,835; 3,617,056; 4,854,575; and 5,180,352 all are illustrative of such prior art While these units may be suitable for the particular purpose to which they address, they would not be as suitable for the purposes of the present invention as heretofore described.
A dumbbell or barbell with generally conventional appearance and means for manual gripping, provided however, with novel identical, uniformly rotatable unbalanced weights. Exercise is achieved by automatically resisting the centrifugal force resulting when the weights are caused to spin.
An exercising device provided which utilizes the precession effect exhibited by masses rotating at a relatively high angular velocity to resist changes in orientation of the axis of rotation. The device contains only the inertial elements which utilize a separate electric motor unit to accelerate the mass, the inertia of which provides the desired effect for several minutes after which it may again easily be accelerated for further use. The acceleration of the mass is accomplished by a clutch on the end of the electric motor shaft which is removably engageable with a rotatably mounted shaft which has the masses mounted thereon. Once the shaft and the mass has been caused to rotate at the required speed the clutch is disengaged from the rotating shaft. The shaft and the masses are rotatably mounted in a housing with a hand grip portion.
A dumbbell is provided which is collapsible for storage and/or convenient transportability and can be expanded, when required for purposes of exercising, by introduction therein of fluid such as water and sand. The dumbbell comprises a hollow, collapsible container comprising a closed loop of hollow tube having an elliptical or doughnut shape, a hollow handle traversing the gap between the inner walls of the closed loop and a fluid inlet provided with a plug seal. The outer peripheral wall of the closed loop is provided with accordion pleats biased into the closed portion but expandable against the bias under the influence of pressure generated by introduction of fluid into the container. The amount of fluid so introduced is a matter of choice of the user to achieve the desired overall weight of the device. Advantageously the dumbbells are integrally molded from thermoplastic resin.
An appliance used in exercising the arms and the legs, comprising a grip covered with a protective sleeve and fastened with an adjustable strap for use in exercising the arms, two sockets attached to said grip at two opposite ends to hold two electronic oscillators and two tapered weights, wherein said counter weights each has a bolt hole for fastening a screw rod at either end of said grip; said caps each has an annular groove for fastening a division plate to secure each electronic oscillator in place, and a tapered opening for fastening either tapered weight; said electronic oscillators are triggered to produce sounds by shock waves.